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Hoppe's #9 gun solvent and Potassium Chloride

  1. Jul 6, 2011 #1
    Hello, my name is Rudy and this is my first post.
    I am a gun owner and I am wondering about how to clean my rifle and all the accumulated residue derived from my military surplus ammunition which has Potassium Chloride in the Primers. After shooting the rifle, the Potassium Chloride gets into the barrel and areas surrounding the bullet shell. This creates a residue which most gun owners simply refer to as salt. But it is specifically, Potassium Chloride. Anyways, there is a lot of unsubstantiated debate on the gun forums over which techniques are most effective at removing the "salt" from their guns. The most common techniques involve water, and/or Windex(which has water and ammonia), and a gun solvent known as Hoppe's #9. IMO, water would work fine to remove "salt' from a gun but then this seems counterintuitive; i.e., using water to prevent gun rust. Of course, those who choose to use water also use gun oils and/or gun solvents after using water to remove the water. Well, after reading dozens of comments on gun forums that go both ways. It is a frustrating experience to read all the conflicting comments from the know-it-alls. I figured it might be a good idea to take this question to a chemistry forum.

    My ultimate question is, can Hoppes#9 gun solvent be sufficient to clean a gun from its usual residue and the Potassium Chloride?

    Here is the list of ingredients of Hoppe's #9 as accurate as i could find online...
    Ethyl Alcohol <35%
    Kerosene <35%
    Trade secret ingredients <25%
    Organic Ester(trade secret) <10%
    Ammonia, aqueous <10%
  2. jcsd
  3. Jul 7, 2011 #2


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    That is an impossible question to answer without experimentation.

    I found on the Hoppes site that #9 solvent also contains oleic acid and amyl acetate. The listed ingredients for #9 look to me to have poor solubilizing power for pure KCl. That isn't the case in powder residue, though, and it is likely that most of the KCl is carried away with the stuff that #9 IS a good solvent/cleaning agent for.

    The #9 Plus contains Hydro-treated (hydrogenated) napthenic distillate (10-30%), ethanol (1-5%), triethanolamine (1-5%), kerosene (1-5%) and triazine (0.5-1.5%). and water. Lots of water. I would say that you should use the #9 plus if you are using corrosive ammo since it contains triethylamine and triazine which are powerful anticorrrosives and it has much more water for solubilizing those salts. The standard #9 doesn't have them.

    #9 Plus is the way to go for you.
  4. Jul 7, 2011 #3
    When a company has been in business as long as Hoppe's, it's because they've been doing something right, i.e., their product works and it has probably been fine-tuned over the years to accommodate chemical changes made to ammunition. Hoppe's #9 solvent is a chemical cocktail concocted to remove the various lubricants and combustion byproducts that result from using a rifle or a gun.

    If the bulk of the combustion residue is in fact potassium chloride (KCl), then there is no better solvent than plain old water, in fact, there is little bit of water in the Hoppe's #9 solvent; it's the 'aqueous' in the ammonia.

    If the build-up of KCl is such that it inhibits loading or seating of a round, I wouldn't hesitate to try and remove it with a little water on a swab or some wadding, FOLLOWED by some Hoppe's to remove the rest of the gunk AND to protect the chamber and the inside of the barrel from oxidation (rust). Water, with or without ammonia, is not sufficient to do the whole job.

    Also, be aware that unprotected steel will rust simply from time and exposure to humidity (water in the air) during storage. See the Hoppe's web site for other products that are designed to help you take care of your firearm investment.

    P.S. - Listen to the voice of experience: use Hoppe's #9 in a well-ventilated area and wash your hands after use. Nervous system damage WILL screw-up your aiming accuracy. See the Materiial Safety Data Sheet at http://www.hoppes.com/msds/Hoppes9/MSDS_Tri-Pac_No_%209_Solvent-Liquid_Revision_1-3.pdf [Broken]
    Last edited by a moderator: May 5, 2017
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